Vehicle fuel tank system for improved crashworthiness

ABSTRACT

A fuel tank system includes a fuel tank and a support structure. The support structure provides impact protection to the fuel tank. The support structure has mounting members, a bottom plate and a support member. The mounting members mount to the vehicle. The bottom plate is provided proximate a bottom wall of the fuel tank, wherein the bottom plate protects the fuel tank from being crushed or punctured and serves as a skid plate if ground contact is made. The support member extends between a respective mounting member and the bottom plate. The support member is configured to fail during impact, allowing the fuel tank to be moved downwardly and laterally by the energy of the impact to a position in which the fuel tank is substantially out of the path of the impact or protected by the chassis of the vehicle.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit from and is a divisional of U.S.application Ser. No. 14/520,676, filed Oct. 22, 2014, entitled VEHICLEFUEL TANK SYSTEM FOR IMPROVED CRASHWORTHINESS, which claims benefit fromand is a continuation of U.S. application Ser. No. 14/149,957, filedJan. 8, 2014, entitled TRUCK FUEL TANK SYSTEM FOR IMPROVEDCRASHWORTHINESS which claims benefit from U.S. Application No.61/750,418, filed Jan. 9, 2103, entitled TRUCK FUEL TANK SYSTEM FORIMPROVED CRASHWORTHINESS, all of which are hereby incorporated byreference in their entirety.

FIELD OF THE INVENTION

The present invention is directed to a fuel system with one or more fueltanks for motor vehicles, including, but not limited to, cars, bussesand heavy duty trucks. More particularly, the invention is directed to afuel tank which is pushed or moved downwardly and/or laterally by theenergy of the impact of an event to a position in which the fuel tank iseither out of the path of the impact or protected by the chassis of thevehicle.

BACKGROUND OF THE INVENTION

It is generally known that in configuring a motor vehicle with a fueltank, it is important to prevent the fuel tank from damage and spillageduring the crash. There are several strategies that have been employedin automotive design to meet those desires and requirements.

Those strategies include, but are not limited to, placing the fuel tankaway from the perimeter of the vehicle, ensuring crush space is providedto absorb crash energy before the fuel tank is affected, constructingthe fuel tank of materials that are not easily cut or torn, applyingshields in areas of the fuel tank that may be vulnerable, routing allsupply lines in protected areas, and providing the filler with a checkvalve to prevent leakage. In addition, many fuel tanks are positioned inlarge cages or structures which are designed to absorb the impact of acrash or event. Other than attempting to absorb the impact, knownsystems do not use the energy of the impact to move the fuel tankdownwardly and/or laterally to a position in which the fuel tank iseither out of the path of the impact or protected by the chassis of thevehicle.

Automobiles and light trucks must pass standards for fuel tank leakagein all mandated crash tests that range from frontal impacts to sideimpacts to rear impacts. However, these standards do not require thatthe fuel tanks be moveable away from the frame of the vehicle during acollision or other such event. In addition, heavy trucks other thanschool buses have no federal requirements for crashworthiness of thefuel system.

Currently, most manufacturers of heavy trucks mount thin wall aluminumor steel tanks to the outside of the frame rails for carrying fuel. Dueto the location and construction of the fuel tanks in heavy trucks, thetank is exposed to crushing during various crash events, resulting in anincreased possibility of fuel spillage, fire and explosion. These risksare a known hazard in fuel storage areas of vehicles and are consideredsignificant if there is an accident causing an object, such as, but notlimited to, debris from an accident or guide rail, to penetrate the fueltank. Rupturing of fuel tanks is believed to be a common reason forfires or explosions.

It would be desirable to provide a vehicle fuel tank system whichovercomes the problems stated above. It would also be desirable toprovide for revised placement and protection for the fuel tanks and fuelsystem, allowing the vehicle and the fuel tanks to manage the energygenerated by a collision or event, such as, but not limited to allowingthe fuel tank to be moved relative to or away from the frame of thevehicle during a collision or similar event, thereby improvingcrashworthiness and reducing the occurrence of tank failure, fuelspillage, fire and/or explosion.

SUMMARY OF THE INVENTION

The invention provides a revised mounting system and a revised locationfor the fuel system and fuel tanks to improve crashworthiness of thevehicle by reducing the occurrence of tank failure, fuel spillage, fireand/or explosion during and after a collision or similar event, whilestill providing a sufficient range for the vehicle. The fuel tanks areprotected from damage from the side, bottom and between the tanks. Thefuel tank mounting system also allows the energy associated with anevent to be managed, such as by allowing the fuel tanks to be pushed ormoved downwardly and/or laterally by the energy of the impact of acollision or similar event to a position in which the fuel tank iseither out of the path of the impact or protected by the chassis orframe of the vehicle.

In one embodiment, a fuel tank system for use with a vehicle isprovided. The fuel tank system includes a fuel tank and a supportstructure. The support structure provides impact protection to the fueltank. The support structure has mounting members, a bottom plate and asupport member. The mounting members mount to the vehicle. The bottomplate is provided proximate a bottom wall of the fuel tank, wherein thebottom plate protects the fuel tank from being crushed or punctured andserves as a skid plate if ground contact is made. The support memberextends between a respective mounting member and the bottom plate. Thesupport member is configured to fail during impact, allowing the fueltank to be moved downwardly and laterally by the energy of the impact toa position in which the fuel tank is substantially out of the path ofthe impact or protected by the chassis of the vehicle.

In one embodiment, a fuel tank system for use with a vehicle isprovided. The fuel tank system includes at least one fuel tank providedproximate frame rail members of the vehicle. The at least one fuel tankhas a top wall positioned proximate a drive shaft of the vehicle. Afirst portion of the at least one fuel tank extends between an extensionof a vertical axis of each of the frame rail members and a secondportion of the at least one fuel tank extending beyond the vertical axisof each of the frame rail members. A support structure has mountingmembers mounted to the frame rail members. The support structureprovides impact protection to the at least one fuel tank. A plate isprovided proximate a bottom wall of the at least one fuel tank, whereinthe plate protects the at least one fuel tank from being crushed orpunctured and serves as a skid plate if ground contact is made. Asupport member extends between a respective mounting member and theplate, the support member is configured to fail during an impact. Anylateral force applied to the at least one fuel tank or the supportstructure during the impact will be partially translated to a downwardforce and a lateral force, causing the at least one fuel tank to bemoved in a direction which is both lateral to the direction of alongitudinal axis of the frame rail members and perpendicular to thedirection of the longitudinal axis of the frame rail members, allowingthe at least one fuel tank to be moved downwardly and laterally by theenergy of the impact to a position in which the fuel tanks are out ofthe path of the impact or protected by a chassis of the vehicle.

In one embodiment, a fuel tank system for use with a motor vehicle isprovided. The fuel tank system includes a fuel tank, a support structureand a guard and a plate. The fuel tank is provided proximate frame railmembers of the motor vehicle. At least a first portion of the fuel tankextends between an extension of a vertical axis of each of the framerail members. A second portion of the fuel tank extends beyond thevertical axis of each of the frame rail members. The fuel tank has a topwall positioned proximate a drive shaft of the vehicle. A supportstructure has mounting members which are mounted to the frame railmembers and which position the fuel tank proximate the frame railmembers, the support structure protects the fuel tank during an impact.A guard is positioned between the fuel tank and the drive shaft toprovide protection of the fuel tank in an event of a failure of thedrive shaft. A plate is provided proximate a bottom wall of the fueltank. A support member extends between a respective mounting member andthe plate. The support member is configured to fail during the impact,allowing the fuel tank to be moved downwardly and laterally by theenergy of the impact to a position in which the fuel tank issubstantially out of the path of the impact or protected by the chassisof the vehicle.

In one embodiment, the fuel tanks are provided beneath the frame railmembers of the vehicle. A support structure may be provided for supporton each side of the vehicle which also acts as a guard for the tank. Abottom plate may also be provided to protect the tanks from intrusionfrom below and protect the tanks in the event of a front axle attachmentfailure and the resulting impact and ground contact. Additionally, aguard section may be positioned between the tanks to provide protectionfor the tanks in the event of a drive shaft or drive line failure.

The use of the support structure provides both impact and tearingprotection for the tank. This support structure also allows mounting ofother components such as exhaust, air tanks and emission control systemsto the outside of the structure. These mounted components will furtheract as energy absorbing members, further protecting the tank. Thesupport structure also allows mounting of additional energy absorbingdevices or structures as needed.

The bottom plate will protect the bottom of the tank from crush orpuncture and serve as a skid plate if ground contact is made. The frontedge of the bottom plate may be turned up to allow for protection to thefront side of the tank or tanks. The bottom plate also provides alocation for mounting and location hardware and brackets for the tank.

The support structure may be mounted to tank locating brackets attachedto the bottom plate. This may be formed in a U-section with wings whichwill serve as tank retention brackets.

Additional protection may be provided by energy absorbing capabilitiesof accessories mounted outside of the tanks and energy absorbingbrackets.

In one embodiment, the fuel lines are routed within the structure andthe frame rails. The tanks would be filled from a tube routed out therear side of the tanks and structure with an integrated check system inthe tank to prevent in the event of failure of this hose.

Other features and advantages of the present invention will be apparentfrom the following more detailed description of the preferredembodiment, taken in conjunction with the accompanying drawings whichillustrate, by way of example, the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of components of an illustrative embodimentof a fuel system according to the present invention.

FIG. 2 is a top view of the fuel system of FIG. 1.

FIG. 3 is a front view of the fuel system of FIG. 1.

FIG. 4 is a side view of the fuel system of FIG. 1.

FIG. 5 is a front perspective view of components of an alternateillustrative embodiment of a fuel system according to the presentinvention, with one of the vehicle frame rail members removed.

FIG. 6 is a perspective view of the components of the alternateillustrative embodiment of a fuel system shown in FIG. 5 with the fueltanks removed and both of the vehicle frame rail members shown.

FIG. 7 is a top view of the fuel system of FIG. 5, with both of thevehicle frame rail members shown.

FIG. 8 is a back perspective view of the fuel system of FIG. 5 with bothof the vehicle frame rail members shown.

DETAILED DESCRIPTION OF THE INVENTION

The description of illustrative embodiments according to principles ofthe present invention is intended to be read in connection with theaccompanying drawings, which are to be considered part of the entirewritten description. In the description of embodiments of the inventiondisclosed herein, any reference to direction or orientation is merelyintended for convenience of description and is not intended in any wayto limit the scope of the present invention. Relative terms such as“lower,” “upper,” “horizontal,” “vertical,” “above,” “below,” “up,”“down,” “top” and “bottom” as well as derivative thereof (e.g.,“horizontally,” “downwardly,” “upwardly,” etc.) should be construed torefer to the orientation as then described or as shown in the drawingunder discussion. These relative terms are for convenience ofdescription only and do not require that the apparatus be constructed oroperated in a particular orientation unless explicitly indicated assuch. Terms such as “attached,” “affixed,” “connected,” “coupled,”“interconnected,” and similar refer to a relationship wherein structuresare secured or attached to one another either directly or indirectlythrough intervening structures, as well as both movable or rigidattachments or relationships, unless expressly described otherwise.Moreover, the features and benefits of the invention are illustrated byreference to the preferred embodiments. Accordingly, the inventionexpressly should not be limited to such preferred embodimentsillustrating some possible non-limiting combination of features that mayexist alone or in other combinations of features, the scope of theinvention being defined by the claims appended hereto.

Referring now to the drawings wherein like reference characters refer tolike and corresponding parts throughout the several views, there isshown in FIGS. 1 through 4 two fuel tanks 10 which are part of a fuelsystem 12 for a motor vehicle, such as, but not limited to, a car, bus,tractor of a tractor trailer truck, other heavy trucks or similar typevehicles. While two fuel tanks are shown, at least one fuel tank orother numbers of fuel tanks may be used without departing from the scopeof the invention.

Each fuel tank 10 can be made in one piece, as shown in the drawings.Alternatively, the fuel tanks can be made using conventional methods,such as, but not limited to, having a bottom pan member and a top panmember joined in any conventional manner, such as by a series ofcontinuous welds which fasten together flanges of the bottom pan memberand the top pan member. The material used to form the fuel tanks can beany material which will not degrade or fail when exposed to the fuel(i.e. diesel) which is stored in the fuel tanks 10, such as, but notlimited to, polyethylene.

An inlet pipe or tube (not shown) is secured to the fuel tank 10, forexample through a top wall 18 of the tank 10. The inlet tube may besecured to the fuel tank 10 in any known manner. The inlet tube is forthe purpose of introducing diesel or other desired fuel into therespective tank 10. The inlet tube may be secured to the fuel tank 10 atvarious locations, including, but not limited to, near the rearward endof the tank 10. A gasoline feed tube or pipe (not shown) extends fromthe fuel tank 10, for example through a bottom wall 22, for the purposeof feeding the fuel to the engine of the vehicle. The feed tube or pipemay be located at various locations, including, but not limited to, nearthe forward end of the tank 10.

As best shown in FIGS. 1 and 3, the tanks 10 are adapted to behorizontally attached to the underside of the truck or vehicle so thatthe top walls 18 and the bottom walls 22 of the tanks are essentiallyparallel to the plane of the longitudinal axis of frame rail members 30of the truck or motor vehicle and essentially parallel to thelongitudinal axis of the drive shaft or drive line (not shown) of thevehicle. It should be understood that the cross section and overallshape of the fuel tanks 10 can be of any desired modification based onthe space available for the tanks 10 and the desired capacity of thetank 10. In the embodiment shown in FIGS. 1 through 4, sloped walls 24,26 (as best shown in FIG. 3) extend from top walls 18. Sloped walls 24are dimensioned to cooperate with mounting members 40, as will be morefully described. Sloped walls 26 are configured to allow the fuel tanks10 to be installed between the frame rail members 30 and proximate tothe drive shaft. This configuration of the sloped surfaces 24, 26 causesthe fuel tanks 10 to be pushed downward and sideways, away from thedrive shaft and away from the frame rail members 30 of the vehicleduring an event, such as, but not limited to, a collision, crash oraccident.

As any force is applied to the fuel tanks 10 during such an event, thesloped surfaces 24, 26 cause the applied forces to exhibit a partialdownward or vertical force and a partial lateral or horizontal force onthe fuel tanks 10, causing the fuel tanks 10 to be moved away from oneor both of the frame rail members 30 of the vehicle and away from thedrive shaft. The movement of the fuel tanks 10 relative to the vehicleand the frame rail members 30 is in a direction which is horizontal orlateral to the direction of the longitudinal axis of the frame railmembers 30, in a direction which is vertical or perpendicular to thedirection of the longitudinal axis of the frame rail members 30, or in adirection which is both horizontal or lateral to the direction of thelongitudinal axis of the frame rail members 30 and vertical orperpendicular to the direction of the longitudinal axis of the framerail members 30. This allows the fuel tanks 10 to be pushed or moveddownwardly and/or laterally by the energy of the impact to a position inwhich the fuel tank is either out of the path of the impact or protectedby the chassis of the vehicle, for example to a position away from oneor more of the frame rail members 30 and the drive shaft of the vehicle.

The system described herein manages the energy created by an event tomanipulate or move the fuel tanks 10 to a position in which the fueltanks 10 are less prone to failure during or after the event therebyimproving crashworthiness and reducing the occurrence of tank failure,fuel spillage, fire and/or explosion.

As best shown in FIG. 1, the fuel system 12 includes the fuel tanks 10,mounting members 40, at least one rail 50 and at least one bottom plate60. The mounting members 40 have an S-shaped configuration with a firstend section 42, a middle section 44 and a second end section 46. Thefirst end section 42 of each mounting member 40 is mounted to arespective frame member 30 of the vehicle using known mounting methods,such as, but not limited to, bolting the first end section 42 to theframe 30. The second end section 46 of each mounting member 40 ismounted to a respective rail 50 using known mounting methods, such as,but not limited to, bolting the second end section 46 to the rail 50.The second end section 46 of each mounting member 40 may also be mountedto the bottom plate 60 using known mounting methods, such as, but notlimited to, bolting the second end section 46 to the bottom plate 60.Alternatively, or additionally, the bottom plate 60 may be mounted tothe rails 50 using known mounting methods, such as, but not limited to,bolting the rails 50 to the bottom plate 60. The rails 50 are mounted tothe mounting members 40 and/or the bottom plate 60 in such a manner toallow for the release of the bottom plate 60 when a force is applied tothe fuel tanks 10 or the mounting members 40 due to an event. Thisallows the fuel tanks 10 to be moved downward and/or sideways relativeto the chassis of the vehicle and/or sideways or lateral relative to oneor more of the frame members 50 to a position in which the fuel tanksare either out of the path of the impact or protected by the chassis ofthe vehicle.

The mounting members 40 may have a nonlinear cross-section to provideadditional strength to the mounting members 40, thereby enhancing theability of the mounting members 40 to support additional weight and toprovide additional crush resistance for the fuel tanks 10. The nonlinearconfiguration of the mounting members 40 allows for forces appliedthereto to be better dissipated over the entire surface of the mountingmembers 40, thereby preventing lateral forces from being transferreddirectly to the fuel tanks 10 during an event, such as, but not limitedto, a collision, crash or accident. The mounting members 40 may be madefrom any material having the strength characteristics desired,including, but not limited to, steel and cross-linked polyethylene.

As best shown in FIG. 3, the middle section 44 is dimensioned to have adownward tilt away from the frame members 30. In one embodiment, theangle of the downward tilt is approximately equal to the slope of thesloped wall 24. Consequently, as a lateral force is applied to themounting members 40, the middle section 44 cooperates with the surface24 causing the lateral force to be partially translated to a downwardforce and a lateral force, causing the fuel tanks 10 to be moveddownward or sideways away from the frame members 30 and the drive shaft.In so doing, the fuel tank 10 is moved away from the drive shaft duringan event, such as, but not limited to, a collision, crash or accident,thereby preventing the fuel tanks 10 from being punctured by the driveshaft. As any force is applied to the mounting members 40 during such anevent, the angled middle sections 44 cause the applied forces to exhibita partial downward force and a partial lateral force on the mountingmembers 40, causing the mounting members 40 and the fuel tanks 10 to bemoved away from one or both of the frame rail members 30 of the vehicleand away from the drive shaft. The movement of the fuel tanks 10relative to the vehicle and the frame rail members 30 is in a directionwhich is horizontal or lateral to the direction of the longitudinal axisof the frame rail members 30, in a direction which is vertical orperpendicular to the direction of the longitudinal axis of the framerail members 30, or in a direction which is both horizontal or lateralto the direction of the longitudinal axis of the frame rail members 30and vertical or perpendicular to the direction of the longitudinal axisof the frame rail members 30. This allows the fuel tanks 10 to be pushedor moved downwardly and/or laterally by the energy of the impact to aposition in which the fuel tanks are either out of the path of theimpact or protected by the chassis of the vehicle, for example to aposition away from one or more of the frame rail members 30 and thedrive shaft of the vehicle.

The spacing of the mounting members 40 along the fuel tanks 10 can bevaried depending upon the capacity of the fuel tanks 10 and the amountof protection required to prevent puncture of the fuel tanks 10 duringor as a result of such an event. Alternatively, the mounting member 40may be a solid member to provide enhanced protection.

As shown in FIG. 3, rails 50 may have a nonlinear cross-section toprovide additional strength to the rails 50, thereby enhancing theability of the rails 50 to provide additional integrity to the system 12and to provide additional crush resistance for the fuel tanks 10. Thenonlinear configuration of the rails 50 allows for forces appliedthereto to be better dissipated over the entire surface of the rails 50,thereby preventing lateral forces from being transferred to the fueltanks 10 during an event, such as, but not limited to, a collision,crash or accident. The rails 50 may be made from any material having thestrength characteristics desired, including, but not limited to, steeland cross-linked polyethylene.

In the illustrative embodiment, the bottom plate 60 extends below theentire width and length of the fuel tanks 10. As shown in FIG. 3, thebottom plate 60 may have a nonlinear cross-section to provide additionalstrengthening ribs 66 to the bottom plate 60, thereby enhancing theability of the bottom plate 60 to provide additional integrity to thesystem 12 and to provide additional crush resistance for the fuel tanks10. The nonlinear configuration of the bottom plate 60 allows for forcesapplied thereto to be better dissipated over the entire surface of thebottom plate 60, thereby preventing damaging forces from beingtransferred to the fuel tanks 10 during such an event. The bottom plate60 may be made from any material having the strength characteristicsdesired, including, but not limited to, steel and cross-linkedpolyethylene. The strengthening ribs 66 may be spaced periodically alongthe bottom plate 60 or may be more uniformly distributed, depending uponthe material used for the bottom plate 60 and the strengthcharacteristics desired.

The bottom plate 60 protects the fuel tanks 10 from intrusion from belowand protects the fuel tanks 10 in the event of a front axle attachmentfailure and the resulting impact and ground contact. The bottom plate 60protects the bottom of the fuel tanks 10 from being crushed or puncturedand serves as a skid plate if ground contact is made. A front edge 62(FIG. 4) of the bottom plate 60 may be turned up to allow for protectionto the front side of the fuel tanks 10. The bottom plate 60 alsoprovides a location for conventional mounting and location hardware andbrackets to mount the fuel tanks 10 to the bottom plate 60. The mountingmembers 40 may also be mounted to the tank locating brackets attached tothe bottom plate 60. In one embodiment, the tank locating bracket may beformed in a U-section with wings which serve as tank retention brackets.

A guard 70 (FIG. 1) may be positioned between the fuel tanks 10 toprovide protection for the tanks 10 in the event of a drive shaftfailure. The guard may be made from any material having the strengthcharacteristics desired, including, but not limited to, steel andcross-linked polyethylene.

An alternate illustrative embodiment is shown in FIGS. 5 through 8. Inthis embodiment, a single fuel tank 110 is shown. While one fuel tank isshown in the system 112, other numbers of fuel tanks may be used withoutdeparting from the scope of the invention. As one illustrative option,the fuel tanks may be modular, allowing the appropriate number of tanksto be used to accommodate the desired fuel capacity. The material usedto form the fuel tanks can be any material which will not degrade orfail when exposed to the fuel (i.e. diesel) which is stored in the fueltank 110, such as, but not limited to, polyethylene.

An inlet pipe or tube 120 is secured to the fuel tank 110, for examplethrough a side wall 119 of the tank 110. The inlet tube may be securedto the fuel tank 110 in any known manner. The inlet tube is for thepurpose of introducing diesel or other desired fuel into the respectivetank 110. The inlet tube may be secured to the fuel tank 110 at variouslocations, including, but not limited to, near the rearward end of thetank 110. As shown in FIG. 6, openings may be provided through the railframe members 130 and the mounting member 140 to allow the inlet pipe120 to access the tank 110. A gasoline feed tube or pipe (not shown)extends from the fuel tank 110, for example through a bottom wall 122,for the purpose of feeding the fuel to the engine of the vehicle. Thefeed tube or pipe may be located at various locations, including, butnot limited to, near the forward end of the tank 110.

As best shown in FIGS. 5 and 8, the tanks 110 are adapted to behorizontally attached to the underside of the truck or vehicle so thatportions 121 of the tanks 110 are positioned between the frame railmembers 130 and cross supports 131 of the truck or motor vehicle. Achannel 133 is provided to accommodate the drive shaft or drive line(not shown) of the vehicle. It should be understood that the crosssection and overall shape of the fuel tank 110 can be of any desiredmodification based on the space available for the tank 110 and thedesired capacity of the tank 110. In the embodiment shown, the railframe members 130 are notched at 141 (as shown in FIG. 6) to allow forthe tank 110 to be positioned between the rail frame members 130. Whenmounted to the rail frame members 130, the combination of the mountingmembers 140, rails 150 and bottom plate 160 provide additional strengthto the rail frame members 130 to compensate for any weakness to the railframe members 130 caused by the notches 141.

The fuel system 112 includes the fuel tank 110, mounting members 140, atleast one rail 150 and at least one bottom plate 160. As best shown inFIG. 8, the mounting members 140 have an S-shaped configuration with afirst end section 142, a middle section 144 and a second end section146. The first end section 142 of each mounting member 140 is mounted toa respective frame member 130 of the vehicle using known mountingmethods, such as, but not limited to bolting the first end section 142to the frame 130. The second end section 146 of each mounting member 140is mounted to the bottom plate 160 using known mounting methods, suchas, but not limited to bolting the second end section 146 to the bottomplate 160. The second end section 146 of each mounting member 140 mayalso be mounted to a respective rail 150 using known mounting methods,such as, but not limited to, bolting the second end section 146 to therail 150. Alternatively, or additionally, the bottom plate 160 may bemounted to the rails 150 using known mounting methods, such as, but notlimited to, bolting the rails 150 to the bottom plate 160. The rails aremounted to the mounting members 140 and or the bottom plate 160 in sucha manner to allow for the release of the bottom plates 160 when a forceis applied to the fuel tank 110 or the mounting members 140 due to anevent. This allows the fuel tank 110 to be pushed or moved downwardlyand/or laterally by the energy of the impact to a position in which thefuel tank is either out of the path of the impact or protected by thechassis of the vehicle, for example to a position away from one or moreof the frame rail members 130 and the drive shaft of the vehicle.

As best shown in FIG. 8, the middle section 144 is dimensioned to have aflange 135 which extends away from the frame members 130. Extending fromthe flange 135 to the bottom plate 160 are one or more support membersor struts 137. The support members or struts 137 provide additionalsupport to the system 112 and maintain the bottom plate 160 in positionrelative to the rail frame members 130 during normal operation. However,in case of an event, such as, but not limited to, a collision, crash oraccident, the support members or struts 137 are designed to fail,causing the bottom plate 160 and the fuel tank 110 to move away from theframe members 130 of the vehicle and the drive shaft. In so doing, thefuel tank 110 is moved away from the drive shaft during such an event,thereby preventing the fuel tank 110 from being punctured by the driveshaft or other parts of the vehicle. The failure of the struts 137 allowthe fuel tank 110 to be moved away from one or both of the frame railmembers 130 of the vehicle and away from the drive shaft. The movementof the fuel tank 110 relative to the vehicle and the frame rail members130 is in a direction which is horizontal or lateral to the direction ofthe longitudinal axis of the frame rail members 130, in a directionwhich is vertical or perpendicular to the direction of the longitudinalaxis of the frame rail members 130, or in a direction which is bothhorizontal or lateral to the direction of the longitudinal axis of theframe rail members 130 and vertical or perpendicular to the direction ofthe longitudinal axis of the frame rail members 130. This allows thefuel tank 110 to be pushed or moved downwardly and/or laterally by theenergy of the impact to a position in which the fuel tank is either outof the path of the impact or protected by the chassis of the vehicle,for example to a position away from one or more of the frame railmembers 130 and the drive shaft of the vehicle.

In the embodiment shown, each mounting member 140 is one piece whichextends along the entire side of the fuel tank 110. However, theconfiguration of the mounting members 140 can be varied depending uponthe capacity of the fuel tank 110 and the amount of protection requiredto prevent puncture of the fuel tank 110 during or as a result of suchan event. For example, the mounting members 140 may be individualmembers rather than a solid member (similar to that shown in FIGS. 1through 4).

As shown in FIGS. 5, 6 and 8, rails 150 may have a nonlinearcross-section to provide additional strength to the rails 150, therebyenhancing the ability of the rails 150 to provide additional integrityto the system 112 and to provide additional crush resistance for thefuel tank 110. The nonlinear configuration of the rails 150 allows forforces applied thereto to be better dissipated over the entire surfaceof the rails 150, thereby preventing lateral forces from beingtransferred to the fuel tanks 110 during such an event. The rails 150may be made from any material having the strength characteristicsdesired, including, but not limited to, steel and cross-linkedpolyethylene.

In the illustrative embodiment, the bottom plate 160 extends below theentire width and length of the fuel tank 110. As shown in FIG. 6, thebottom plate 160 may have a nonlinear cross-section to provideadditional strengthening ribs 166 to the bottom plate 160, therebyenhancing the ability of the bottom plate 160 to provide additionalintegrity to the system 112 and to provide additional crush resistancefor the fuel tank 110. The nonlinear configuration of the bottom plate160 allows for forces applied thereto to be better dissipated over theentire surface of the bottom plate 160, thereby preventing damagingforces from being transferred to the fuel tank 110 during an event, suchas, but not limited to, a collision, crash or accident. The bottom plate160 may be made from any material having the strength characteristicsdesired, including, but not limited to, steel and cross-linkedpolyethylene. The strengthening ribs 166 may be space periodically alongthe bottom plate 160 or may be more uniformly distributed, dependingupon the material used for the bottom plate 160 and the strengthcharacteristics desired.

The bottom plate 160 protects the fuel tank 110 from intrusion frombelow and protects the fuel tank 110 in the event of a front axleattachment failure and the resulting impact and ground contact. Thebottom plate 160 protects the bottom of the fuel tank 110 from beingcrushed or punctured and serves as a skid plate if ground contact ismade. One or more front plates 163 (FIG. 6) may be attached or integralto the bottom plate 160 and/or the mounting members 140 and/or the rails150 may be provided to allow for additional protection to the front sideof the fuel tank 110. The bottom plate 160 also provides a location forconventional mounting and location hardware and brackets to mount thefuel tank 110 to the bottom plate 160. The mounting members 140 may alsobe mounted to the tank locating brackets attached to the bottom plate160. In one embodiment, the tank locating bracket may be formed in aU-section with wings which serve as tank retention brackets.

A guard (not shown, but similar to that shown in FIGS. 1 through 4) maybe positioned in the channel 133 to provide protection for the tank 110in the event of a drive shaft failure. The guard may be made from anymaterial having the strength characteristics desired, including, but notlimited to, steel and cross-linked polyethylene.

As shown in the illustrative embodiments of FIGS. 1 through 8, the framemembers 30, 130, mounting members 40, 140, rails 50, 150 and the bottomplate 60, 160 form a protective area, cage or support area whichprovides a crush-free zone for the fuel tank(s) 10, 110. The supportstructure may be provided for support on each side of the vehicle whichalso acts as a guard for the fuel tank(s) 10, 110. The use of thesupport structure provides both impact and tearing protection for thefuel tank(s) 10, 110. This support structure also allows mounting ofother components such as exhaust, air tanks and emission control systemsto the outside of the structure. These mounted components will furtheract as energy absorbing members, further protecting the fuel tanks. Thesupport structure also allows mounting of additional energy absorbingdevices or structures as needed.

The invention, as shown and described with respect to the illustrativeembodiments, provides a revised mounting system and a revised locationfor the fuel system and fuel tanks to improve crashworthiness of thevehicle by reducing the occurrence of tank failure, fuel spillage, fireand/or explosion during and after a collision or similar event, whilestill providing a sufficient range for the vehicle. The fuel tanks areprotected from damage from the side, bottom and between the tanks. Thefuel tank mounting system also allows the energy associated with anevent to be managed, such as by allowing the fuel tanks to be pushed ormoved downwardly and/or laterally by the energy of the impact of acollision or similar event to a position in which the fuel tank iseither out of the path of the impact or protected by the chassis orframe of the vehicle.

While the invention has been described with reference to a preferredembodiment, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted forelements thereof without departing from the spirit and scope of theinvention as defined in the accompanying claims. In particular, it willbe clear to those skilled in the art that the present invention may beembodied in other specific forms, structures, arrangements, proportions,sizes, and with other elements, materials, and components, withoutdeparting from the spirit or essential characteristics thereof. Oneskilled in the art will appreciate that the invention may be used withmany modifications of structure, arrangement, proportions, sizes,materials, and components and otherwise, used in the practice of theinvention, which are particularly adapted to specific environments andoperative requirements without departing from the principles of thepresent invention. The presently disclosed embodiments are therefore tobe considered in all respects as illustrative and not restrictive, thescope of the invention being defined by the appended claims, and notlimited to the foregoing description or embodiments.

The invention claimed is:
 1. A fuel tank system for a vehicle, the fueltank system comprising: a fuel tank; a support structure which providesimpact protection to the fuel tank, the support structure havingmounting members, a bottom plate, and a support member, the mountingmembers mount to the vehicle, the bottom plate provided proximate abottom wall of the fuel tank, wherein the bottom plate protects the fueltank from being crushed or punctured and serves as a skid plate ifground contact is made, the support member extending between arespective mounting member and the bottom plate; and wherein the supportmember is configured to fail during an impact, allowing energy appliedduring the impact to the support structure to be translated to avertical force and a lateral force, pushing the fuel tank in a directionwhich is lateral to the direction of a longitudinal axis of the framerail members and perpendicular to the direction of the longitudinal axisof the frame rail members, allowing the fuel tank to be moved verticallyand laterally by the energy of the impact to a position in which thefuel tank is substantially out of the path of the impact or protected bythe chassis of the vehicle into a vertical force and a lateral force. 2.The fuel tank system of claim 1, wherein the fuel tank has sloped wallswhich extend from a top wall positioned proximate the vehicle.
 3. Thefuel tank system of claim 1, wherein portions of the mounting membersare sloped.
 4. The fuel tank system of claim 1, wherein the mountingmembers have nonlinear cross-sections to provide additional strength tothe mounting members.
 5. The fuel tank system of claim 1, wherein thebottom plate has a leading edge which is turned up to allow forprotection of the fuel tank.
 6. The fuel tank system of claim 1, whereina guard is positioned between the fuel tank and a drive shaft of thevehicle to provide protection of the fuel tank in the event of a failureof the drive shaft.
 7. A fuel tank system for a vehicle, the fuel tanksystem comprising: at least one fuel tank provided proximate frame railmembers of the vehicle, the at least one fuel tank having a top wallpositioned proximate a drive shaft of the vehicle, a first portion ofthe at least one fuel tank extending between an extension of a verticalaxis of each of the frame rail members and a second portion of the atleast one fuel tank extending beyond the vertical axis of each of theframe rail members; a support structure having mounting members whichare mounted to the frame rail members, the support structure providesimpact protection to the at least one fuel tank; a plate providedproximate a bottom wall of the at least one fuel tank, wherein the plateprotects the at least one fuel tank from being crushed or punctured andserves as a skid plate if ground contact is made; a support memberextending between a respective mounting member and the plate, thesupport member configured to fail during an impact; and wherein alateral force applied during the impact to the at least one fuel tank orthe support structure will be partially translated to a vertical forceand a lateral force, causing the at least one fuel tank to be moved in adirection which is both lateral to the direction of a longitudinal axisof the frame rail members and perpendicular to the direction of thelongitudinal axis of the frame rail members, allowing the at least onefuel tank to be moved vertically and laterally by the energy of theimpact to a position in which the fuel tanks are out of the path of theimpact or protected by a chassis of the vehicle.
 8. The fuel tank systemof claim 7, wherein the at least one fuel tank is adapted to behorizontally attached to the underside of the vehicle, such that the topwall of the at least one fuel tank is essentially parallel to ahorizontal plane of a longitudinal axis of the frame rail members andessentially parallel to a longitudinal axis of the drive shaft.
 9. Thefuel tank system of claim 7, wherein portions of the mounting membersare sloped away from the respective frame rail member to which themounting members are attached, wherein the portions of the mountingmembers are configured to push the at least one fuel tank to be movedaway from the frame rail members in response to the impact applied tothe support structure.
 10. The fuel tank system of claim 9, wherein themounting members have nonlinear cross-sections to provide additionalstrength to the mounting members.
 11. The fuel tank system of claim 7,wherein the plate has a leading edge which is turned up to allow forprotection of the at least one fuel tank.
 12. The fuel tank system ofclaim 7, wherein a guard is positioned between the at least one fueltank and the drive shaft to provide protection for the at least one fueltank in the event of a failure of the drive shaft.
 13. The fuel tanksystem of claim 7, wherein the support structure includes rails mountedto the mounting members, the rails having a nonlinear cross-section toprovide additional strength to the rails which provides integrity to thesystem and provides crush resistance for the fuel tank, the nonlinearcross-section of the rails allowing for forces applied to the rails tobe dissipated over a surface of the rails, thereby protecting the tankfrom the energy of the impact.
 14. A fuel tank system for use with amotor vehicle, the fuel tank system comprising: a fuel tank providedproximate frame rail members of the motor vehicle, at least a firstportion of the fuel tank extending between an extension of a verticalaxis of each of the frame rail members and a second portion of the fueltank extending beyond the vertical axis of each of the frame railmembers, the fuel tank having a top wall positioned proximate a driveshaft of the vehicle; a support structure having mounting members whichare mounted to the frame rail members and which position the fuel tankproximate the frame rail members, the support structure protects thefuel tank during an impact; and a plate is provided proximate a bottomwall of the fuel tank, a support member extends between a respectivemounting member and the plate, the support member is configured to failduring the impact, allowing the fuel tank to be moved vertically andlaterally of a longitudinal axis of the frame rail members by the energyof the impact to a position in which the fuel tank is substantially outof the path of the impact or protected by the chassis of the vehicle.15. The fuel tank system of claim 14, wherein respective mountingmembers are positioned on either side of the fuel tank, each respectivemounting member being a one piece member which extends along an entireside of the fuel tank.
 16. The fuel tank system of claim 14, wherein thesupport structure includes rails mounted to the mounting members. 17.The fuel tank system of claim 16, wherein the rails having a nonlinearcross-section to provide additional strength to the rails which providesintegrity to the system and provides crush resistance for the fuel tank,the nonlinear cross-section of the rails allowing for forces applied tothe rails to be dissipated over a surface of the rails, therebyprotecting the fuel tank from the energy of the impact.